[Python] Use an empty class to hold a temporary scope

def function_creator():
   class FnScope:
     b = 5
     c = 6
   def inner_fn():
      FnScope.b += 1
      FnScope.c += FnScope.b
      print(FnScope.c)
   return inner_fn

>>> f = function_creator()
>>> f()
12
>>> f()
19
>>> f()
27

Reference: Python nested functions variable scoping